The invention relates generally to a medical device such as an automated or semi-automated external defibrillator (AED), and more particularly to a defibrillator that can turn on, turn off, or turn both on and off automatically, a case for storing the defibrillator, a system that includes the defibrillator and the case, and related methods.
AEDs have saved the lives of many patients who have suffered cardiac arrest in non-hospital settings, and, as a result of advances in AED technology, the number of lives saved per year is rising. An AED is a battery-operated device that analyzes a patient""s heart rhythm, and, if appropriate, administers an electrical shock (automated) or instructs an operator to administer an electrical shock (semi-automated) to the patient via electrode pads. For example, such a shock can often revive a patient who is experiencing ventricular fibrillation (VF).
Because cardiac arrest can cause permanent damage or death within a short time if left untreated, an AED operator should be able to set up and activate an AED within seconds after the operator arrives at the scene. Statistically, for each minute that the patient is in cardiac arrest and is not receiving cardiopulmonary resuscitation (CPR), his chance of survival decreases by 10%. And in most cases, there is no chance for resuscitation after 10 minutes. Unfortunately, many people do not know how to administer CPR. And, even in the best of circumstances, it can take a few minutes to retrieve the AED and a few additional minutes for the AED to diagnose and shock the patient. Therefore, even if the patient is discovered immediately, the operator often has little time to set up and activate the AED without further decreasing the patient""s chance of survival. Clearly, the faster the operator can activate and set up the AED, the better the chances that the patient will survive.
Unfortunately, with the continued proliferation of easily accessed AEDs, it is increasingly likely that an operator will have little or no experience using a particular brand of AED and/or may panic during a resuscitation attempt, and thus may waste valuable seconds trying to figure out how to turn on, i.e., activate, an AED. Although an entity such as an airline may provide AEDs in its places of business and train its employees to operate them, an employee typically uses these AEDs so infrequently that his skills may become xe2x80x9crustyxe2x80x9d even if the entity offers periodic refresher courses. Furthermore, non-employees such as airline passengers may have no formal training in the use of an AED; consequently, the first time that such a person operates an AED may be during a resuscitation attempt. Now although an AED will often xe2x80x9cwalkxe2x80x9d an operator through the steps of resuscitation once the AED is activated, the operator typically must determine how to activate the AED on his own. Unfortunately, the operator""s xe2x80x9crustinessxe2x80x9d or lack of training coupled with the anxiety induced by the resuscitation effort may make it difficult for the operator to determine how to activate the AED. Furthermore, the label of the AED""s on/off switch may be confusing to the operator, and thus may exacerbate his difficulty in determining how to activate the AED. For example, the on/off switch may use a xe2x80x9c1xe2x80x9d to indicate xe2x80x9conxe2x80x9d, and a xe2x80x9c0xe2x80x9d to indicate xe2x80x9coff.xe2x80x9d But although xe2x80x9c1xe2x80x9d and xe2x80x9c0xe2x80x9d are touted as being xe2x80x9cuniversalxe2x80x9d on and off symbols, respectively, they are often unrecognizable to an operator without electronics or computer experience. And although the AED may use the words xe2x80x9conxe2x80x9d and xe2x80x9coffxe2x80x9d or their non-English equivalents to label the switch, these words may be unrecognizable to an operator who speaks another language or may be difficult to see under non-optimal lighting conditions.
General Overview of an AED
FIG. 1 is a perspective view of a conventional AED system 10, which includes an AED 12 for generating a defibrillation shock and defibrillator electrode pads 14a and 14b for providing the shock to a patient (not shown). A connector 16 couples the electrode pads 14a and 14b to a receptacle 18 of the AED 12. Typically, the electrode pads 14a and 14b are sealed within a package (not shown) that an operator (hands shown in FIG. 1) tears or peels open to access the electrode pads 14a and 14b. The package acts as a moisture barrier that prevents the electrode-pad contact gel (not shown) from prematurely drying out during storage of the electrode pads 14a and 14b. A battery 19, which typically is a lithium-based battery, can provide relatively high power so that the AED 12 can quickly generate the defibrillation shock. The battery 19 and AED 12 may be stored separately, with the operator connecting the battery 19 to the AED 12 just prior to use in an emergency. Or preferably, the battery 19 and AED 12 may be stored together, with the battery 19 connected to the AED 12 during storage. For example, the battery 19 is often disposed inside of the AED 12 until it needs to be replaced.
The AED 12 includes a housing 21, a main on/off switch 20, a display 22 for displaying operator instructions, cardiac waveforms, or other information, a speaker 24 for providing audible operator instructions or other information, status light-emitting diodes (LEDs) 26, a status indicator 28, and a shock button 30, which the operator presses to deliver a shock to the patient (not shown). The AED 12 may also include a microphone 32 for recording the operator""s voice and other audible sounds that occur during the rescue, and non-volatile memory such as a data card 34 for storing these sounds along with the patient""s ECG and a record of AED events for later study.
Still referring to FIG. 1, during an emergency where it is determined that the patient (not shown) may need a shock, the operator retrieves the AED 12, then presses the on/off switch 22 to activate the AED 12. Once activated, the AED 12 displays instructions on the display 24 and/or xe2x80x9cspeaksxe2x80x9d instructions via the speaker 26. Following these instructions, the operator removes the electrode pads 14a and 14b from the protective package (not shown) and inserts the connector 16 into the receptacle 18. Then, the operator places the electrode pads 14a and 14b on the patient in the respective positions shown in the pictures on the pads and on the AED 12. After the operator places the electrode pads 14a and 14b on the patient, the AED 12 analyzes the patient""s ECG to determine whether the patient is suffering from a shockable heart rhythm. If the AED 12 determines that the patient is suffering from a shockable heart rhythm, then it instructs the operator to depress the shock button 30 to deliver a shock to the patient. Conversely, if the AED 12 determines that the patient is not suffering from a shockable heart rhythm, it informs the operator to seek appropriate non-shock treatment for the patient and disables the shock button 30 so that even if the operator presses the button 30, the AED 12 does not shock the patient.
As discussed above, the operator""s inexperience, anxiety, and/or his inability to read the label of the switch 20 may delay the activation, and thus the set up and use, of the AED 12. Unfortunately, this delay may reduce the patient""s chance of survival by increasing the time that he is in cardiac arrest.
Consequently, a need exists for an AED that activates automatically when needed to resuscitate a patient.
In one embodiment of the invention, a defibrillator includes a housing and an activator disposed or attached to the housing. The activator activates the defibrillator when the housing moves from a predetermined location.
Such a defibrillator can be designed such that it activates automatically when an operator removes it from a storage location. This automatic activation often decreases the time it takes the operatorxe2x80x94particularly an inexperienced or anxious operatorxe2x80x94to set up and use the AED, and thus often increases a patient""s chance of survival by reducing the time that he is in cardiac arrest.
In another embodiment of the invention, a defibrillator includes a housing and a deactivator disposed or attached to the housing. The deactivator deactivates the defibrillator when the housing is disposed in a predetermined location.
Such a defibrillator can be designed such that it deactivates automatically when an operator returns it to a storage location.
In yet another embodiment of the invention, a defibrillator includes a housing and an activator/deactivator disposed or attached to the housing. The activator/deactivator activates the defibrillator when the housing moves from a predetermined location and deactivates the defibrillator when the housing is disposed in the predetermine location.